1. Field of the Invention
The present invention relates to a mobile telecommunication system. In particular, the present invention relates to a mobile telecommunication system and a method thereof for high-speed acquisition of paths by detecting and outputting a plurality of multi-peaks.
2. Background of the Related Art
In general, the signals from a sender are transmitted to a receiver using multiple communication paths or multi-path because of reflection from buildings and geographical features possible on a single communication path or transmission channel. The receiver searches a main path and a multi-path at the same time, using a pilot signal acquisition device that includes a matched filter. A detector often used in the acquisition device can be a multi-peak detector. The multi-peak detector accumulates and sorts out a plurality of energy values that have been converted by the receiver. At this time, the multi-peak detector should be equipped with one chip maskable in order to get rid of any neighboring energy values within one chip.
FIG. 1 is a block diagram of a related art acquisition device. With reference to FIG. 1, the acquisition device provides a matched filter 101 with the signals having I and Q components that are inputted at the receiving end. The matched filter 101 then calculates the despreading value on each I and Q component signals, and provides the result to a squarer 103. The squarer 103 sends the energy value obtained through squaring and adding the despreading value to an energy calculator 105. The energy calculator 105 adds a previous energy value to a current energy value inputted in sequence and saves the sum. A peak detector 113 reads a number of the energy values that are saved cumulatively into the energy calculator 105 one by one, and detects an energy value having the highest peak value.
The matched filter 101, the squarer 103 and the energy calculator 105 in the acquisition device constitute hardware 100, and the peak detector 113 constitutes software 110. However, the related art multi-peak detector of FIG. 1 has numerous energy values that are usually calculated by the hardware, and the software including the multi-peak detector 113 has to spend a great deal of time to read corresponding code phases and to sort and decide. A Code Division Multiple Access (CDMA) system that has very complex functions cannot sufficiently allocate the processing speed of the software for energy detection, and accordingly, the software cannot complete the peak detection within a short period of time.
For example, suppose that the resolution for search during a slot synchronizing procedure of acquisition step 1 as defined in the W-CDMA mobile telecommunication system is ½chip, and the total number of code phase is 5120. In a case where the related art multi-peak software is used, the software had to read every code phase, and perform the sorting and the masking for 5120 code phases, respectively. To do so, a large number of slots are used, and other functions of the CDMA modem are significantly delayed or come to a halt during the operation. Further, deciding the peak energy value by reading up to 5120 code phases by a single software is not that practical in itself.
The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.